Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0005684 (bladder cancer)
 16,431 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Photodynamic therapy (PDT) is an established anticancer modality and hypericin is a promising photosensitizer for the treatment of bladder tumors. We show that exposure of bladder cancer cells to hypericin PDT leads to a rapid rise in the cytosolic calcium concentration which is followed by the generation of arachidonic acid by phospholipase A2 (PLA2). PLA2 inhibition significantly protects cells from the PDT-induced intrinsic apoptosis and attenuates the activation of p38 MAPK, a survival signal mediating the up-regulation of cyclooxygenase-2 that converts arachidonic acid into prostanoids. Importantly, inhibition of p38alpha MAPK blocks the release of vascular endothelial growth factor and suppresses tumor-promoted endothelial cell migration, a key step in angiogenesis. Hence, targeted inhibition of p38alpha MAPK could be therapeutically beneficial to PDT, since it would prevent COX-2 expression, the inducible release of growth and angiogenic factors by the cancer cells, and cause an increase in the levels of free arachidonic acid, which promotes apoptosis.
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PMID:Targeted inhibition of p38alpha MAPK suppresses tumor-associated endothelial cell migration in response to hypericin-based photodynamic therapy. 1621 8

Angiogenesis is critical for growth of tumors and their metastasis. In this article we review the literature on studies of angiogenesis pathways and markers for renal cancer, prostate cancer and bladder cancer. Overall, there is clear evidence that markers of angiogenesis and expression of angiogenic factors are associated with adverse outcomes in each of these tumor types. Relatively few angiogenic pathways have been investigated so far, although over 50 factors are known to be involved, and little has been studied on the antiangiogenic pathways and their suppression. The failing in many of the studies is small size and lack of suitable statistical analysis. Nevertheless, this review demonstrates the importance of these pathways and the need to develop selection criteria for patients who are candidates for antiangiogenic therapies. On the basis of the expression profiles reported so far, therapies that target vascular endothelial growth factor should be considered for the treatment of renal, prostate and bladder cancers. As most tumors express factors that are involved in multiple angiogenic pathways, further research is needed to determine which are coregulated and what the most common patterns are.
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PMID:Mechanisms of disease: angiogenesis in urologic malignancies. 1652 88

Hypoxia-inducible factors (HIF-1alpha and HIF-2alpha) are closely related protein complexes that activate transcription of target genes in response to hypoxia. The immunohistochemical expression of these two proteins was investigated in 144 bladder cancer tissue samples and correlated with standard clinicopathological features, in order to elucidate their prognostic significance. We also evaluated their possible associations with other angiogenesis related markers such as microvessel density (MVD), vascular endothelial growth factor, thymidine phosphorylase, tenascin, fibronectin, p53 and bcl-2 to further clarify their implication in tumor stroma vascularization. Nuclear HIF-1alpha expression in tumor cells was detected in 57.1% of the cases. A trend of correlation of this expression with poorly differentiated tumors was observed. In addition, HIF-1alpha expression was positively correlated with stromal cells thymidine phosphorylase expression. Tumors that were progressed in muscle-infiltrating disease showed a higher HIF-1alpha expression. A higher HIF-1alpha expression was also observed in tumors with an in situ component. In tumor cells, low HIF-2alpha expression was observed in 6.3%, moderate in 31.9% and high in 61.8% of the cases. A trend of correlation of this expression with MVD was observed. In addition, HIF-2alpha expression was positively correlated with thymidine phosphorylase and fibronectin expression. A lower HIF-2alpha expression was detected in tumors that recurred earlier in univariate methods of analysis. HIF-2alpha was expressed in tumor stroma associated cells in 53.5% of specimens and was correlated with advance tumor stage, thymidine phosphorylase and tenascin expression. There was no statistically significant difference in the expression of both HIF-1alpha and HIF-2alpha between primary and recurrent tumors. In multivariate analysis including T stage, T grade, multifocality and T size, both HIF-1alpha and HIF-2alpha expression were not considered dependent in the prediction of recurrence or progression. In conclusion, the results of the present study indicate that HIF-1alpha and HIF-2alpha expression may help to predict recurrence or progression to muscle invasive disease but not as independent prognostic factors. In addition, the expression of HIF-1alpha and HIF-2alpha, appear to play a role in bladder cancer, vascularization possibly and in cooperation with other angiogenic factors.
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PMID:Hypoxia-inducible factors HIF-1alpha and HIF-2alpha expression in bladder cancer and their associations with other angiogenesis-related proteins. 1703 15

In a recent study, we showed that the proteasome inhibitor bortezomib sensitizes human bladder cancer cells to IFN-induced cell death. Here, we characterized the molecular mechanisms underlying the antitumoral effects of the combination in more detail. Bortezomib synergized with IFN-alpha to promote apoptosis via a tumor necrosis factor-related apoptosis-inducing ligand-associated mechanism but did not inhibit production of proangiogenic factors (vascular endothelial growth factor, basic fibroblast growth factor, and interleukin-8) in human UM-UC-5 cells. In contrast, exposure to the combination did not increase the levels of apoptosis in human UM-UC-3 cells but did inhibit the production of basic fibroblast growth factor and vascular endothelial growth factor. Studies with tumor xenografts confirmed that combination therapy with bortezomib plus IFN-alpha was effective in both models but that the effects were associated with differential effects on tumor necrosis factor-related apoptosis-inducing ligand-associated apoptosis (predominant in UM-UC-5) versus inhibition of angiogenesis (predominant in UM-UC-3). Together, our results show that combination therapy with IFN-alpha plus bortezomib is effective but can work via different mechanisms (apoptosis versus angiogenesis inhibition) in preclinical models of human bladder cancer.
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PMID:Combination therapy with IFN-alpha plus bortezomib induces apoptosis and inhibits angiogenesis in human bladder cancer cells. 1717 6

Bladder cancer mortality varies between the countries; whereas being highest in Western countries, it is lowest in Eastern countries, such as India. Cigarette smoking is one of the major risk factors for bladder cancer in affluent nations, such as United States. Localized early-stage bladder cancer is treated with resection and intravesical cytokine therapy, whereas metastatic cancer is typically treated with various combinations of systemic chemotherapy. Whether curcumin, a yellow curry pigment commonly consumed in countries, such as India, has any role in prevention or treatment of bladder cancer was investigated. We found that curcumin inhibited the proliferation, induced cell cycle arrest, and DNA fragmentation in both IFN-alpha-sensitive (RT4V6) and IFN-alpha-resistant (KU-7) bladder cancer cells. Curcumin also potentiated the apoptotic effects of the chemotherapeutic agents (gemcitabine and paclitaxel) and of cytokines [tumor necrosis factor (TNF) and TNF-related apoptosis-inducing ligand]. This effect of curcumin was independent of sensitivity and resistance to IFN-alpha, commonly used for treatment of bladder cancer. Whether the effects of curcumin are mediated through modulation of the nuclear factor-kappaB (NF-kappaB) pathway known to mediate antiapoptosis was investigated. Both gemcitabine and TNF activated NF-kappaB in bladder cancer cells and curcumin suppressed this activation. Similarly, cigarette smoke, a major risk factor for bladder cancer, also activated NF-kappaB and curcumin suppressed it. Cigarette smoke-induced expression of the NF-kappaB-regulated gene products cyclooxygenase-2 and vascular endothelial growth factor, linked with proliferation and angiogenesis, respectively, was also down-regulated by curcumin.
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PMID:Curcumin potentiates the apoptotic effects of chemotherapeutic agents and cytokines through down-regulation of nuclear factor-kappaB and nuclear factor-kappaB-regulated gene products in IFN-alpha-sensitive and IFN-alpha-resistant human bladder cancer cells. 1736 95

Due to the poor prognosis of advanced bladder carcinoma and the insufficient affects of the chemotherapy agents for this disease, the investigation of the novel genetic and pharmacologic agents including anti-angiogenic agents that can target pathway-specific molecules has been the subject of several publications especially for the last 2 years. Although the clinical trials of these agents are still lacking, the experimental and the preliminary studies are giving hope for the future treatment of advanced bladder carcinoma. Sunitinib malate and sorafenib are the novel food and drug administration (FDA) approved anti-angiogenic agents, which have recently been demonstrated to improve the progression-free survival in patients with metastatic renal cell carcinoma. The main mechanism of these two drugs are defined as preventing the tumor growth by the inhibition of angiogenesis and the induction of apoptosis and necrosis via acting on different types of vascular endothelial growth factor (VEGF) such as the several agents which have been demonstrated to be beneficial for bladder carcinoma. According to this knowledge we suggest that these two new agents may also increase the progression-free survival of the patients with advanced bladder carcinoma due to their anti-angiogenic and tumor cell apoptotic effects. We believe that the evaluation of the effects of these agents on bladder cancer population by clinical, prospective and placebo controlled studies may prove our hypothesis and add critical findings to the literature which is still lacking.
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PMID:Sunitinib malate and sorafenib may be beneficial at the treatment of advanced bladder cancer due to their anti-angiogenic effects. 1736 54

Several authors have investigated the antitumor activity of angiotensin II type 1 receptor (AT1R) antagonists, which are widely used as antihypertensive drugs. In this study, we evaluated the efficacy of the AT1R antagonist candesartan against bladder cancer. For the study in vitro, human bladder cancer cells (KU-19-19) were cultured with and without angiotensin II (A II) and candesartan, and cell viability and vascular endothelial growth factor (VEGF) secretion were analyzed. Also for the study in vivo, a tumor xenograft model was prepared in nude mice using KU-19-19 cells. Mice were administered candesartan daily by oral gavage, and paclitaxel via intravenous infusion. Microvessel density, VEGF expression, and apoptosis were investigated. Candesartan did not induce direct toxicity in KU-19-19 cells, but VEGF was significantly lower in candesartan-treated cells than in the A II-treated control cells. In mice, candesartan, paclitaxel and candesartan-paclitaxel significantly suppressed tumor growth to 46.0%, 35.8% and 17.3%, respectively, of the tumor volume in the control group, showing that combined treatment significantly inhibited tumor growth compared to the candesartan group. Microvessel density and VEGF were significantly decreased in the candesartan and candesartan-paclitaxel groups compared to the control group. The apoptotic index was significantly increased in the paclitaxel and candesartan-paclitaxel groups compared to the control and candesartan groups. In our experimental model, candesartan prevented bladder cancer growth by inhibiting angiogenesis. Furthermore, combined treatment with candesartan and paclitaxel enhanced paclitaxel-induced cytotoxicity. These results suggest that the AT1R antagonist candesartan may be a candidate for innovative therapy for bladder cancer.
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PMID:Effect of angiotensin II type 1 receptor antagonist on tumor growth and angiogenesis in a xenograft model of human bladder cancer. 1750 71

Hepatocyte growth factor (HGF) receptor Met and hypoxia-inducible factor-1 (HIF-1) signaling pathways are commonly activated in aggressive tumors and promote progression. Since both Met and HIF-1alpha proteins are heat shock protein (Hsp) 90 clients, Hsp90 inhibitors might be expected to positively impact tumor progression. Here, we systematically evaluated the inhibitory effects of the prototypical Hsp90 inhibitor geldanamycin (GA) on cellular processes involved in invasion and angiogenesis in T24 bladder cancer cells stimulated with HGF and chemical hypoxia. First, we demonstrated the positive feedback loop between Met and HIF-1 pathways, which serves to sustain and amplifies their signaling in T24 cells. GA downregulated Met by inhibiting new protein maturation, thereby dampening HGF signaling. HGF and chemical hypoxia with CoCl2 cooperatively promoted in vitro invasion and vascular endothelial growth factor (VEGF) secretion, while CoCl2 but not HGF activated urokinase-type plasminogen activator and matrix metalloproteinase 2, both of which promote invasion and angiogenesis. Low dose GA (100 nmol/L) inhibited these processes by suppressing both HGF and HIF-1 pathways. Notably, brief GA pretreatment inhibited in vitro invasion and VEGF secretion induced by HGF as effectively as did continuous treatment. Moreover, we found that GA inhibited activation of focal adhesion kinase, focal adhesion assembly, and actin reorganization induced by HGF and integrin engagement by extracellular matrix. Thus, GA widely suppresses extrinsic stimuli-induced signaling that contribute to tumor invasion and angiogenesis in this bladder carcinoma model, suggesting the utility of Hsp90 inhibitors in preventing tumor progression and metastasis.
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PMID:Low dose geldanamycin inhibits hepatocyte growth factor and hypoxia-stimulated invasion of cancer cells. 1752 27

Recently, two single nucleotide polymorphisms in the hypoxia-inducible factor-1 alpha (HIF-1 alpha) gene, P582S and A588T, were shown to cause significantly higher transcriptional activity than the wild type. We investigated the association between the HIF-1 alpha polymorphisms and the incidence and progression of transitional cell carcinoma of the bladder, and the relationship between the polymorphisms and the tissue vascular endothelial growth factor (VEGF) level or microvessel density (MVD). A total of 219 patients with bladder cancer and 464 healthy native Japanese control subjects were enrolled. Tissue VEGF and HIF-1 alpha expression levels and the mean MVD were evaluated in 73 radical cystectomy specimens by immunohistochemistry. The HIF-1 alpha genotype did not significantly influence the incidence or disease status of bladder cancer. Among patients who underwent radical cystectomy, those with a variant allele had significantly worse disease-free survival (p = 0.001) and disease-specific survival (p = 0.006) than those without a variant allele. Multivariate analysis using a Cox proportional hazard model revealed that the presence of a variant allele was an independent predictor of disease-free survival (HR = 3.10, 95%CI = 1.38-6.99, p = 0.006). Although not statistically significant, the moderate/high expression levels of VEGF in tumor tissues were more frequently observed in patients with a HIF-1 alpha variant allele (11/13, 84.6%) than in those without (33/60, 55%, p = 0.063). The HIF-1 alpha polymorphisms may have a significant influence on the poor prognosis of the patients undergoing radical cystectomy for bladder cancer, while they seem to have no relation to the bladder cancer occurrence.
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PMID:Prognostic significance of HIF-1 alpha polymorphisms in transitional cell carcinoma of the bladder. 1800 Aug 26

The purpose of this study was to evaluate the diagnostic efficacy of urinary transforming growth factor-beta1 (TGF-beta1) and vascular endothelial growth factor (VEGF) in comparison with voided urine cytology in the detection of bladder cancer. This study included 120 patients with bladder cancer, 54 patients with benign urological disorders and 55 healthy volunteers. Urine supernatant was used for estimation of TGF-beta1 and VEGF by ELISA. VEGF was detected by Western blot (WB) analysis in the urine supernatant of randomly selected bladder cancer patients. The urine sediment was used for cytology. There was a statistically significant difference in the median levels of TGF-beta1 (P=0.002) and VEGF (P=0.000) between the control, benign and malignant groups. The concordance rate of VEGF ELISA with VEGF WB was 96.3%. The overall sensitivity and specificity were 70.8% and 90.8% for voided urine cytology, 71.6% and 59.6% for TGF-beta1, and 76.7% and 61.5% for VEGF. The combined use of voided urine cytology with TGF-beta1 and VEGF improved the sensitivity up to 94.9%, although it lowered specificity to 62.0%. There was a significant association between positivity rate of TGF-beta1 and positive urine cytology samples (P=0.023). Median level and positivity rate of VEGF were significantly associated with early stage (I, II) of bladder carcinoma (P=0.01 and 0.025, respectively). Our data indicate that urinary TGF-beta1 and VEGF had higher sensitivities compared to voided urine cytology. Moreover, the combined sensitivity of voided urine cytology with TGF-beta1 and VEGF together was higher than sensitivity of voided urine cytology alone in detection of bladder cancer.
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PMID:The diagnostic efficacy of urinary TGF-beta1 and VEGF in bladder cancer: comparison with voided urine cytology. 1804 65


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